The objective of the proposed research is to examine how neighborhood and school contexts structure the romantic and sexual relationships that are formed during adolescence. Neighborhoods and schools shape exposure to informal social control, perceptions of early childbearing, and beliefs about romantic and sexual relationships. Studying relationship formation processes and characteristics and the ways in which neighborhoods and schools structure them is a key step towards better understanding subgroup variation in reproductive health and family formation. Although there is a large literature on neighborhood effects, and to a lesser extent, school effects, on sexual and contraceptive behavior, early childbearing, and sexually transmitted infections (STIs), and a small but growing literature on the importance of romantic and sexual relationships for these outcomes, no prior research has examined the role of neighborhood and school contexts in shaping these romantic and sexual relationships. The proposed inquiry investigates how neighborhood and school contexts, specifically, the sociocultural characteristics of these contexts, influence the selection of partners and the types of relationships that are formed during adolescence. To achieve our objective, we will analyze Waves I and III of the National Longitudinal Study of Adolescent Health (Add Health), which includes data on adolescents' neighborhood and school contexts and on adolescents' subsequent relationship experiences. The specific aims are to: 1) investigate the effects of neighborhood and school sociocultural contexts on the characteristics of adolescents' romantic and sexual relationships; and 2) examine the interactive effects between neighborhood and school sociocultural contexts on the characteristics of adolescents' romantic and sexual relationships. The proposed study will use ecometric methods to create neighborhood and school sociocultural measures and will employ multilevel modeling techniques to account for the nested structure of the data. PUBLIC HEALTH RELEVANCE: Understanding adolescents' romantic and sexual relationships and the ways in which neighborhood and school contexts influence the characteristics of these relationships is relevant to population health because these early life course experiences affect their reproductive health and set the stage for future family formation choices and behaviors. The study findings will provide new information regarding the role of neighborhoods and schools in structuring young people's relationships and will benefit policy and community-level programmatic strategies aimed at promoting sexual health and reducing the risk of unintended pregnancies and sexually transmitted infections.